The disclosure relates generally to sleeping bags, and more particularly, to sleeping bags having an inner blanket selectively moveable from a closed configuration to an opened configuration relative to an inner volume of the sleeping bags.
Typically, sleeping bags are used when conventional bed and bedding are unavailable. For example, sleeping bags are used by backpackers, hikers, campers, mountaineers, and other users as portable beds or coverings. Sleeping bags are often durable sleeping coverings that provide a soft surface, insulation, and weather resistance.
Consumers may face a difficult task in finding a sleeping bag that is thermally efficient, comfortable, and lightweight. One type of sleeping bag is referred to as a “mummy bag”, which tends to be shaped with a lateral taper to approximate the contour of the body of a user and thereby minimize the internal volume of the bag. Mummy bags attempt to conserve heat by minimizing air movement within and from the bag. As a result, mummy bags are often suited for use in outdoor, colder ambient temperatures. For some conventional mummy bags, users may feel discomfort due to the tight fit of the bag. Some users may become too warm or the air within the bag may become stagnant. Such feeling of discomfort may be increased in the body portion of the bag due to the length relative to the rest of the bag. Thus, some users may be unable to sleep comfortably in mummy bags.
Moreover, mummy bags typically have a small generally elliptical opening suitable for a user's head to protrude from during use. In order to enter typical mummy bags, a user must unzip the bag, and then get inside the bag. Due to the tight fit, the user may find it difficult to fully zip the bag, and furthermore, the zipped bag may be uncomfortable. An additional drawback to the mummy bag is that the tight fit of the bag may reduce the range of motion of the user of the bag. Such feeling of discomfort may be increased in parts of the user's body that are often moved during sleep such as the arms and legs of the user.
Other sleeping bags, such as rectangular-type sleeping bags, are shaped with a generally constant lateral dimension and provide a greater range of motion for the user. Such bags also typically have a zippered portion to allow the user to more easily enter the bag. Although rectangular bags are often more spacious than mummy bags, a drawback is that the larger internal volume may reduce the thermal efficiency of the bag. Moreover, rectangular bags often do not insulate the head, and are typically too large to be thermally efficient. As a result, rectangular bags tend to be better suited for use indoors or in milder outdoor temperatures. Although thermally different than mummy bags, rectangular-type sleeping bags may also become too warm or the air within the bag may become stagnant.
Accordingly, a need exists for a sleeping bag that can easily, and efficiently adapt to differing temperatures experience by the user during use of the sleeping bag. Additionally, a need exists for sleeping bag that provides different and movable layers for the user. Moreover, a need exists for a sleeping bag that is both comfortable, thermally efficient, and allows the warm, stagnant air within the bag to escape and be replaced with fresh, ambient air. Still further, a need exists for a sleeping bag that facilitates a greater range of motion for the user.